The Maharal further explained (Gevurot Hashem, Chapter 34) that the order of the plagues came to reveal Hashem's dominion and providence over all parts of creation. This is his wording: "Additionally, one can say regarding those reasons mentioned there, that the plagues came specifically in this order and not in another order. When Pharaoh did not believe in Him, as it is said: 'Who is Hashem that I should heed His voice? I do not know Hashem' (Shemot 5:2), all the plagues came upon him to make His name known to the Egyptians, as it is written (Shemot 7:5), 'And the Egyptians shall know that I am Hashem.' Therefore, the plagues came in this manner.

First, He informed him that He, blessed be He, rules the world, and He started with the water, which is the Nile, because He wanted to start with something that is completely beneath the earth, as water is lower than the earth, as it is written (Shemot 20:4), 'and that is in the water below the earth.' And it is written (Tehillim 24:2), 'For He has founded it upon the seas and established it upon the rivers.' He showed Pharaoh that He, blessed be He, rules over this, and therefore the Nile was struck.

When Pharaoh did not repent, thinking perhaps His dominion is only over the lowest of the low, He brought frogs upon them, creatures that dwell in the water, which are of a higher level than the water itself, because the water is a place for the creatures that are within it. Therefore, the water is lower than the creatures within the water, and the frogs are higher.

Pharaoh still said, perhaps His dominion is no higher, so the dust was struck, becoming lice, which is on the earth, as it is written (Shemot 8:12), 'Strike the dust of the earth and it shall become lice.'

Then He brought upon them the wild beasts, creatures that dwell on the earth, just as He struck the water and then the creatures that dwell in the water. So first, He struck the dust, and then He struck those that dwell on it, which are the wild beasts, predatory animals that dwell on the earth.

After that, when Pharaoh still did not repent, He brought the plague, which is a corruption of the air, a higher realm, in the air of the earth.

Then He brought boils upon them, a plague of fire, which is higher than the air, because boils are from the heat, created by fire. The Holy One, blessed be He, brings fire from the element of fire, and from this, a person gets boils.

Hail is even higher, as it comes from the atmospheric heavens. However, the locusts are even higher, as they are birds, and they fly in the firmament of the heavens, which is the atmospheric firmament, as known. It has already been explained above that anything which is a place for something else is lower and more humble than the thing that dwells there. This is a simple matter in everything, that the place is lower in level than what dwells there. The heavens are the dwelling place for birds, as it is written (Bereishit 1:6), 'Birds shall fly above the earth across the firmament of the heavens.' And it is said (Yechezkel 38:20), 'And the birds of the heavens.' Therefore, first came the hail from the heavens. Then the locusts, in the atmospheric firmament. Then the darkness, in the luminaries, which are in the upper heavens. Finally, the plague of the firstborn, which strikes the human soul, a spiritual matter, and this is higher, because the luminaries are physical, but the soul is spiritual. Then the Israelites left, because it was then known to the Egyptians that He, blessed be He, rules below the earth and in the heavens above. Below the earth are the waters beneath the earth, and in the heavens above is the soul, which is above the heavens." Thus concludes the Maharal's explanation.